Incazelo Yenqubo Yokuhlanganisa I-SMT PCB

I-SMT (ubuchwepheshe bokufaka izinto eziphezu komhlaba) iyindlela evelele yokuhlanganisa amabhodi esifunda esimanje: izingxenye zifakwa ngqo kuma-pad ebusweni bebhodi bese zihlanganiswa ngasikhathi sinye kuhhavini ophinda ugeleze. Yilokho okwenza kube nokwenzeka ukusebenzisa ama-elekthronikhi amancane, aminyene, anevolumu ephezulu namuhla. Lo mhlahlandlela uchaza ukuthi iyini i- SMT PCB nokuthi umugqa wokuhlanganisa usebenza kanjani isinyathelo ngesinyathelo, ukuthi ukufakwa kwezinto eziphezu komhlaba kuqhathaniswa kanjani nembobo edlulayo, amaphakheji ezingxenye ezivamile, indlela yokuklama ibhodi elihlangana kahle, nokuthi amabhodi aqediwe ahlolwa futhi ahlolwe kanjani.

Kusho ukuthini i-SMT nokuthi kungani ibusa

Kubuchwepheshe bokufaka phezu komhlaba, izingxenye zineziphetho ezincane noma ama-lead ahlanganisa ngqo ama-pad ebusweni bebhodi, kunokuba kube yimilenze edlula emigodini ebholiwe. Ibhodi lingathwala izingxenye zombili izinhlangothi, futhi yonke inhlangano ihlanganiswa nge-solder ngesikhathi esisodwa nge-oven ephinda igeleze.

I-SMT ibusa ngezizathu ezicacile. Izingxenye zokufaka phezulu zincane kakhulu kunezimbobo zazo ezilingana nazo, ngakho-ke amabhodi aminyene futhi ancane kakhulu. Le nqubo izenzakalelayo kakhulu, okwenza isheshe, iphindaphindeke, futhi ingabizi kakhulu. Futhi isekela amaphakheji ane-pitch encane, ane-pin-count ephezulu adingwa ama-chip anamuhla. Cishe kuzo zonke izinto zikagesi zamanje, i-SMT iyinto ezenzakalelayo, yingakho ikhono eliyinhloko le-assembler liwumugqa wayo we-SMT, inhliziyo ye- PCB assembling.

Umugqa Wokuhlanganisa we-SMT, Isinyathelo Ngesinyathelo

Umugqa we-SMT uwuchungechunge lwemishini, ngayinye yenza umsebenzi owodwa bese idlulisela ibhodi komunye. Ukuqonda ukugeleza kwenza imithetho yokuklama ibe nomqondo kamuva.

1. Ukuphrinta kwe-solder-paste

I-stencil yensimbi engagqwali ibekwe phezu kwebhodi elingenalutho, bese kuthi i-solder paste, ingxube yezinhlayiya ezincane ze-solder kanye ne-flux, icindezelwe ngezimbobo ezise-stencil ziye kuma-pad. Izimbobo ze-stencil zilawula ngqo ukuthi ingakanani i-paste ewela ku-pad ngayinye, futhi ukuthola lelo nani elifanele kuyisisekelo samajoyinti amahle.

2. Ukuhlolwa kokunamathisela nge-solder (SPI)

Uhlelo oluzenzakalelayo luhlola i-paste ephrintiwe, ivolumu, indawo, kanye nesimo kuphedi ngayinye, ngaphambi kokuba noma yiziphi izingxenye ziwe. Ukubamba inkinga ye-paste lapha kushibhile kakhulu kunokuthola iphutha ngemva kokugeleza kabusha, ngakho-ke i-SPI iyisango lekhwalithi elibalulekile emsebenzini we-fine-pitch.

3. Khetha bese ubeka

Imishini yesivinini esikhulu ikhetha izingxenye ezivela kuma-reels nasemathileyi bese izibeka ngqo kuma-pad anamathiselwe, izinkulungwane zezindawo ngehora. Ukuqina kwe-paste kugcina ingxenye ngayinye endaweni yayo kuze kube yilapho ihlanganiswa nge-solder. Ukunemba kokubekwa yikho okuvumela izingxenye ezincane nama-chips amancane ukuthi ahlanganiswe ngokuthembekile.

4. I-Reflow soldering

Ibhodi eligcwele abantu lihamba kuhhavini ophinda ugeleze ngephrofayili yokushisa elawulwa ngokucophelela, lifudumale, licwiliswe, libe phezulu lincibilikise i-solder (kuma-alloy angenalo i-lead, libe phezulu cishe ngo-245 °C), bese liphola. I-paste iyancibilika bese yakha amalunga e-solder, bese iqina njengoba ibhodi liphola. Iphrofayili yokushisa ihlelwe ebhodini kanye nezingxenye zalo, futhi ama-substrate adinga ukunakwa okukhethekile, yingakho amabhodi asindayo ngokushisa eqhutshwa ngamaphrofayili afanele ukuhlanganiswa kwensimbi.

5. Ukuhlolwa okuzenzakalelayo kokukhanya kanye ne-X-ray

Ngemva kokugeleza kabusha, ukuhlolwa okuzenzakalelayo kwe-optical (AOI) kuhlola amalunga abonakalayo kanye nokubekwa kwezingxenye ngamakhamera. Kumaphakheji axhumene nawo angaphansi komzimba, njenge-QFN kanye ne-BGA, ukuhlolwa kwe-X-ray kusetshenziselwa ukubona amalunga afihliwe. Ndawonye ziqinisekisa ukuthi ukunamathela kuphume kahle.

6. Amabhodi anezinhlangothi ezimbili

Uma izingxenye zihamba zombili izinhlangothi, uhlangothi olukhanyayo luvame ukuhlanganiswa kuqala, bese ibhodi liphendulwa bese kuthi uhlangothi lwesibili luqhutshwe, izingxenye ezisindayo kakhulu zibekwe ohlangothini lokugcina ukuze zingaphazanyiswa. Lokhu kulandelana kugcina konke kusendaweni yakho ngesikhathi sokugeleza kabusha kwesibili.

I-SMT vs Imbobo Ehamba Ngayo

Ukufakwa kobuso akukayishintshi ngokuphelele imbobo edlulayo; ngayinye inendawo yayo, futhi amabhodi amaningi asebenzisa womabili.

Imbobo edlulayo isathola indawo yayo yezixhumi ezithatha umthwalo womshini, izingxenye zamandla amakhulu, nanoma yini ezuzayo ngama-lead abanjwe ebhodini. Imikhiqizo eminingi yangempela iyi -hybrid : izingxenye ezifakwa ngaphezulu ziyageleza kabusha kuqala, bese izingxenye zembobo edlulayo zengezwa ngokushintsha okukhethiwe noma nge-wave soldering. I-assembler enekhono isebenzisa zombili izinqubo ebhodini elilodwa, okubalulekile njengoba imiklamo iqhubekela ekuhlanganisweni kwe-PCB okunomthamo omkhulu.

Izinhlobo Ezivamile Zephakheji Ye-SMT

Izingxenye ze-SMT ziza ngamaphakheji ahlukahlukene, futhi indlela ngayinye ehlolwa ngayo incike ekutheni amalunga ayo ayabonakala yini.

Iphethini ilula: izingxenye ezinezintambo ezibonakalayo (i-SOIC, i-QFP) kanye nama-chip passives zihlolwa ngokubona, kuyilapho amaphakheji e-bottom-terminated kanye ne-ball-grid (i-QFN, i-BGA) efihla amalunga azo futhi edinga i-X-ray. Ukwazi lokhu ngaphambili kubumba uhlelo lokuhlola kanye nomklamo, izingxenye ze-fine-pitch kanye ne-hidden-joint zidinga ukulawulwa kwenqubo okuqinile.

Ukuklama iBhodi Elilungele i-SMT

Ibhodi elihlanganiswa kahle lenzelwe ukuhlanganiswa, hhayi nje ukusebenza. Amaphuzu abalulekile okuklama ukukhiqiza yilawa:

• Izinyathelo ezifanele kanye namaphethini omhlaba. Amaphedi kumele afane nephethini enconywa yingxenye; izinyathelo ezingalungile zibangela ukubekwa kanye nokukhubazeka kokunamathela.
• Izimbobo zokunamathisela ezinengqondo kanye nomklamo we-stencil. Izimbobo ze-stencil kumele zibeke ivolumu efanele yokunamathisela, ikakhulukazi ezingxenyeni ezithambile neziqediwe phansi.
• Ama-fiducial. Izimpawu zokubhekisela zivumela imishini ukuthi ivumelane ngokunembile, nezimpawu zendawo zamadivayisi asebenzisa iphimbo elincane.
• Isikhala esanele. Shiya isikhala phakathi kwezingxenye ukuze zibekwe, ziphinde zigeleze, futhi zihlolwe.
• Ama-panelization kanye nama-tooling rails. Faka amaphaneli ngokuhlakanipha ngama-rails ukuze ibhodi lihambe kahle emgqeni.
• I-laminate efanele. Sebenzisa into enezinga lokushisa lokushintsha kwengilazi (Tg) elifanele amazinga okushisa angenalo i-lead.
• Ukuphathwa komswakama (MSL). Ezinye izingxenye kumele zibhakwe futhi ziphathwe ngokucophelela ngaphambi kokuphinde zigeleze ukuze kugwenywe umonakalo womswakama.

Ukuzilungisa ngaphambi kokwenza lokhu kuvimbela izinkinga eziningi zokuhlanganisa. Isibuyekezo samahhala se-DFM somkhiqizi sihlola izinyathelo zakho, isikhala, ama-fiducial, kanye nokufakwa kwamaphaneli ngokumelene nomugqa wangempela we-SMT futhi siphawula izinkinga ngenkathi zisashibhile ukuzilungisa. Ikhwalithi yebhodi elingenalutho nayo ibalulekile, njengoba ukuhlanganiswa kuhle kuphela njengokwenziwa kwe -PCB ngaphansi kwalo, futhi imiklamo yesivinini esikhulu noma ye-RF yengeza izidingo ezengeziwe ezihlobene nokukhiqizwa kwe-PCB okusheshayo kanye nezinto zokulahlekelwa okuncane.

Iphrofayili Yokugeleza Kabusha, Isigaba Ngesigaba

I-oven egelezayo yilapho kwakheka khona amalunga e-solder, futhi iphrofayili yayo yokushisa ihlelwe ebhodini kanye nezingxenye zalo. Iphrofayili evamile ihamba ngezigaba ezine.

Ukuthola isigaba ngasinye silungile kubalulekile: i-ramp esheshayo kakhulu ingalimaza izingxenye noma ibangele amaphutha, ukucwilisa okuncane kakhulu kushiya ukushisa okungalingani, kanti ukuphakama okungalungile kunikeza amalunga abuthakathaka noma abandayo. Iphrofayili incike kubunzima bebhodi nezinto zokwakha, yingakho ama-substrate asinda ngokushisa adinga amaphrofayili aklanyelwe ukusetshenziswa ekuhlanganisweni kwensimbi ne-core.

Ama-alloy e-Solder: awanawo umthofu futhi anama-lead

Iningi lokukhiqiza kwamanje lisebenzisa i-solder engenalo i-lead, ngokuvamile i-alloy ye-tin-silver-copper (SAC), encibilikisa ukushisa kakhulu ngakho-ke idinga i-peak ephezulu yokugeleza kanye ne-laminate ekalwe ngayo. I-solder ene-lead (tin-lead) iyancibilika ekushiseni okuphansi futhi isasetshenziswa kwezinye izinhlelo zokusebenza ezikhethekile. I-alloy isetha izinga lokushisa eliphakeme futhi ithonya ukukhetha kwezinto, ngakho-ke inqunywa eceleni kwe-laminate yebhodi ngesikhathi sokukhiqiza i-PCB.

Ukuhlolwa, Ukuhlolwa, kanye Nekhwalithi

Ikhwalithi emugqeni we-SMT yakhelwe ngaphakathi ngokuhlolwa ezigabeni eziningana futhi iqinisekiswa ngokuhlolwa ekugcineni.

Ukuhlolwa ngesikhathi senqubo

• SPI iqinisekisa i-solder paste ngaphambi kokubeka.
• I-AOI ihlola indawo kanye namalunga abonakalayo ngemva kokugeleza kabusha.
• X-ray ihlola amalunga afihliwe amaphakheji e-QFN ne-BGA.

Ukuhlola ibhodi eliqediwe

• Ukuhlolwa okusebenzayo inika amandla ibhodi futhi iqinisekise ukuthi liziphatha njengoba liklanyelwe.
• Ukuhlolwa kwe-In-circuit (ICT) or ukuhlolwa kwe-flying-probe ihlola amanethi ngamanye kanye nezingxenye ngogesi.

Ukuhlolwa nokuhlolwa kwezendlalelo ngale ndlela kuthola amaphutha kusenesikhathi futhi kuqinisekisa ukuthi ibhodi liyasebenza ngaphambi kokuba lithunyelwe. Njengoba ivolumu ikhula, ukulawulwa kwenqubo yezibalo kugcina umugqa uhambisana ukuze ibhodi ngalinye liziphathe njengelokuqala, umehluko phakathi kokwakhiwa okukodwa kanye nokukhiqizwa okuthembekile.

Ukuhlanganiswa kwe-SMT kuyindlela eqondile, ezenzakalelayo, enamathisela, ehlola, ebeka, ephinda igeleze, ehlola, ephendula ibhodi elingenalutho kanye ne-reel yezingxenye zibe umkhiqizo oqediwe. Yakhelwe leyo nqubo kusukela ekuqaleni, futhi umphumela uhlangana kahle futhi uvivinye kahle. Ungafunda kabanzi mayelana ne-Highleap Electronics kanye namakhono ethu okuhlanganisa e-SMT kanye ne-hybrid.

imibuzo ejwayelekile ukubuzwa

Imele ini i-SMT?

Ubuchwepheshe bokufaka phezu komhlaba. Izingxenye zifakwa kuma-pad ebusweni bebhodi bese zihlanganiswa kuhhavini ophinda ugeleze, kunokuba zibe nama-lead adlula emigodini ebholiwe. Ivumela ukuhlanganiswa okuncane, okuxineneyo, okuzenzakalelayo kakhulu futhi ilawula izinto zikagesi zesimanje.

Yiziphi izinyathelo zokuhlanganiswa kwe-SMT?

Ukuphrinta nge-solder-paste nge-stencil, ukuhlolwa kwe-solder-paste (SPI), ukukhetha nokubeka izingxenye, ukugeleza kabusha kwe-solder nge-oven elawulwa ukushisa, kanye nokuhlolwa okuzenzakalelayo kwe-optical kanye ne-X-ray. Amabhodi anezinhlangothi ezimbili aqala ngohlangothi olukhanyayo, bese ephenduka bese egijima ohlangothini lwesibili.

Kungani izingxenye ze-BGA ne-QFN zidinga ukuhlolwa kwe-X-ray?

Ukuxhumeka kwabo kwe-solder kuhlala ngaphansi kwephakheji, ama-BGA kugridi yamabhola, ama-QFN emaphethelweni angezansi, ngakho amakhamera awakwazi ukubona amalunga. Ukuhlolwa kwe-X-ray kubheka iphakheji ukuqinisekisa amalunga afihliwe akhiwe kahle.

Ingabe izingxenye ze-SMT kanye nezingxenye ezimbobo zingaba ebhodini elifanayo?

Yebo, futhi imikhiqizo eminingi iyi-hybrid. Izingxenye ezifakwa ebusweni ziyaphinde zigeleze kuqala, bese izingxenye ezifakwa emgodini zingezwa ngokukhetha noma ngokugoqa ngamagagasi. Imbobo edlulayo igcinelwa izixhumi, izingxenye ezinamandla aphezulu, kanye nezingxenye ezithatha ukucindezeleka komshini.

Yini eyenza kube lula ukuhlanganisa ibhodi nge-SMT?

Izinyathelo ezifanele, izimbobo zokunamathisela eziklanywe kahle, ama-fiducial okuqondanisa, isikhala esanele phakathi kwezingxenye, ukwakheka okunengqondo ngama-rails, i-laminate elinganiswe amazinga okushisa okuphinde ageleze, kanye nokuphathwa okufanele komswakama. Ukubuyekezwa kwe-DFM ngaphambi kokwenziwa kuqinisekisa ukuthi lokhu kulungile.

Ibhodi le-SMT elihlanganisiwe lihlolwa kanjani?

Ukuhlolwa ngesikhathi senqubo (i-SPI, i-AOI, kanye ne-X-ray yamalunga afihliwe) kubamba amaphutha okunamathela, futhi ibhodi eliqediwe liqinisekiswa ngokuhlolwa okusebenzayo, futhi lapho lisetshenziswa, ukuhlolwa kwe-in-circuit noma kwe-flying-probe. Ukulawulwa kwenqubo yezibalo kugcina imiphumela ihambisana nevolumu.